Steam boiler



June 26, 1923.

1,459.86! l. TODD STEAM BOILER Filed Sept. 30, 1920 2 Sheets-Sheet 1 WITNESSE; a 15AACTDD mvsrvron.

J flflpamdl ATTORNEY 1. TODD STEAM BOILER June 26, 1923.

30 1920 2 Sheets-Sheet 2 Filed Sept.

ISAAC TODD IN NTOR- WITNESSES.

ATTORNEY Patented June 26, 1923.

PATENT cr mes.

ISAAC TODD, or .ennrnsr', IRELAND.

s'rneia BOILER.

Application filed September 30, 1920. 3 Serial No. 413,766.

To all whom it may concern:

Be it known that I, ISAAC Tool), of 22 Mountcollyer Avenue, Belfast, Ireland, a subject of the King of Great Britain and Ireland, have invented certain new and useful Improvements in Steam Boilers, of which the following is a specification.

This invention relates tosteam boilers and its object is to provide improvements therein.

Under my invention I provide an improved device for circulating water in a steam boiler, said device comprising a pump casing, a tubular member attached to the 5 boiler and supporting said casing at the normal water level in the boiler, a pipe leading from the interior of said casing to the bottom of the water space, a pump in said casing, a spindle extending from the pump through said tubular member and means for imparting motion thereto, whereby water is drawn through said pipe from the bottom of the water space and is discharged by said pump near the surfaces in the boiler where the heat is greater.

The pump or water lifting device draws the water from one part of the water space at the coolest part of the boiler and discharges it at another part thereof, in proximity or on to a heating surface or sur faces.

The object of circulating the water as described is to pass as much of same as pos sible over the furnace plates and to keep changing the water around the plates continuously so that more'heat is taken up by the water than if the water were lying dead.

around the furnace plates. The continuous circulation of the water around the heating surfaces causes the steam to be made more gently, and less water is liable to be carried over with the steam when the boiler is being forced for steam. Usually the steam is generated violently over the fire and furnace plates, and water is sometimes carried over with the steam in large quantities and passed to the engine from which it returns to the boiler as cold feed.

The invention will now be described with reference to the accompanying drawings, whereon:

Fig. 1 is a cross sectional view of a horizontal steam boiler having two furnaces and showing the water circulating device there- 1n.

Fig. 2 is a sectional plan view on the line a;00, Fig. 1, of a portion of the boiler and showing the water circulating device.

Fig. 3 is a cross sectional view of a horizontal marine steam boiler having three furnaces and showing the water circulating device in position in the boiler.

Fig. 4: is a sectional elevation of the boiler shown at Fig. 3. I

In carrying out my invention as shown at Figs. 1 and 2, I employ a pump a in a casing a located near the crowns of the furnace c and at, or about, the normal w ter level in the boiler. A pipe Z) puts the casing a? into communication with the dead water space at the bottom of the boiler cZ. ater is drawn through the pipe 6 into the casing by the action of the pump a and it is discharged therefrom through orifices in the casing, on to or near the crowns or in the vicinity of the furnaces 0 thereby brushing away the film'of water which clings to the furnace plates and is one of the main losses of heat. One authority (Austin) gives this as .004 of one inch in thickness, hence the necessity for a pump to wash away this layer. The resistance of the plate itselfis insignificant in comparison with the resistance of this film of stagnant water. The screw of the pump a is shown secured to a spindle a which passes through a pipe (1 and stuffing box e to the outside of the boiler.

The tube a is screwed at one end to the stuffing box 6 and at its other end to the cover a of the pump casing (i A pulley f is securedv on the spindle a and may be driven by a belt or otherwise from any suitable source of power.

In the form of the invention illustrated in Figs. 3 and 4.- the pump is shown near the tops of the combustion chambers. It communicates with the dead water space by a pipe I) and is driven from the exterior of the boiler as described with reference to Figs. 1 and 2. If desired, the pump may be located near the. furnace crowns as in the previous arrangement.

Having now fully described my invention what I claim and desire to secure by Letters Patent is In a steam boiler, a water circulating.

and, at the other end, tosaid oover, means pulley on said spindle, outside the boiler, 10 securing said Cover to said pump casing all substantially as set forth. so as to leave discharge orifices therebe- In testimony whereof I affix my signatween, a pipe leading from the interior of ture in presence of tWo Witnesses. said casing to the bottom of the Water space of the boiler, a pump rotatably mounted in ISAAC TODD said caslng, a spindle for said pump e'X- Witnesses: tending through sald tubular member, 9. ANDRE HAMILTON, steam tight joint round said spindle, and a EDWARD HARVEY. 

